It's a .020 TD and have started it several times. The best performance was 17,000 with a 4.5 x 2 Cox prop. May have missed the actual peak so maybe 18,000 or so. The longest run was about a minute and 40 seconds. That seemed short so I checked the tank by pulling the back plate off and it was dry. Is that a normal run for this engine with the plastic tank? I have seen YouTube video's where the .020 models are running over 5 minutes, but maybe not on the stock tank. What is the capacity of the tank? What size tank should I consider? 1/3 to 1/2 oz is my guess. Suspect the tank may have leaked but only when running.